Multiple spin echoes in spin polarized Fermi liquids

Bedford, A.; Bowley, R. M.; Owers‐Bradley, J. R.; Wightman, D.

doi:10.1007/bf00682194

Cited by 14 publications

(5 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In these experiments the occurrence of multiple echos is attributed to nonlinear terms in the equation of motion governing the magnetization. In Fermi liquids, the non-linearity is introduced by the Leggett-Rice effect [37,39]. This effect plays no role in our experiments.…”

mentioning

confidence: 89%

See 1 more Smart Citation

Echo trains in pulsed electron spin resonance of a strongly coupled spin ensemble

Weichselbaumer,

Zens,

Zollitsch

et al. 2018

Preprint

View full text Add to dashboard Cite

mentioning

confidence: 89%

“…This effect plays no role in our experiments. Another source for non-linear terms in the Bloch equations is the dipolar demagnetizing field [39]. The demagnetizing field is usually negligible in ESR and NMR experiments, as it is suppressed by radiation damping [40,41].…”

mentioning

confidence: 99%

Echo trains in pulsed electron spin resonance of a strongly coupled spin ensemble

Weichselbaumer,

Zens,

Zollitsch

et al. 2018

Preprint

View full text Add to dashboard Cite

“…Clearly there is excellent agreement between theory and experiment, there being only one adjustable parameter, that being the height of the first echo at t~ = 0. Further details of the theory and of our results have been given by Bedford et aL 13 We I I I I I I I I ~ I I I 10 100 500 TEMPERATURE (mK) Fig. 9.…”

Section: Resultsmentioning

confidence: 99%

A pulsed NMR study of 3He-4He solutions

et al. 1992

Self Cite

View full text Add to dashboard Cite

We report a study of the Leggett-Rice effect in dilute 3He-4He solutions at a Larmor frequency of 71 MHz. We have measured the height and phase of the spin echoes following 2-pulse NMR sequences of three solutions with 3He concentrations of 0.56%, 1.4%, and 4.00/o. The theory of Leggett fits the data extremely well and yields values of the parameter pMo and the transverse diffusion coefficient D. We are also able to evaluate ItMo and D by analyzing multiple spin echoes and find good consistency between the two methods. From values of 7;/(1 + F~) at various concentrations, we are able to determine the scattering length for 3He quasiparticles, a, quite accurately. We find a = -0.97 4-0.03 ~.

show abstract

“…Those terms could lead to zero soundlike oscillations of density and to longitudinal spin modes, but collisionless Landau damping makes propagation of such waves impossible. In the case of transverse modes the terms in question would (12) result in small virial corrections in the spectrum, and Landau damping turns out to be exponentially small in the long wavelength limit.…”

Section: F Lkl -(N Int a -N H )Li (0) Ni K + ~«Oxhrfr -//°V/*a] -N^rxmentioning

confidence: 99%

“…Spin dynamics of a quantum Fermi liquid of particles with spin y (electrons in metals, liquid 3 He, dilute 3 He- 4 He mixtures, etc.) has been studied in detail both in theory and experiment (e.g., see [1][2][3][4][5][6][7][8][9][10][11][12]). A remarkable fact is that weakly damped collective oscillations of magnetization can propagate in a polarized paramagnetic fluid even in the low density limit and at high temperatures, i.e., in rarefied Maxwell-Boltzmann gases [13][14][15][16][17].…”

mentioning

confidence: 99%

Quadrupole spin oscillations in polarized rarefied media

Bashkin

Puzyrko

1993

Phys. Rev. Lett.

View full text Add to dashboard Cite

A new branch of weakly damped collective magnetic excitations in spin-polarized low-density systems is predicted. This type of wave corresponds to the transverse oscillations of the macroscopic quadrupole moment while the magnetization does not oscillate. The spectra of both spin waves and quadrupole modes are calculated. The theory can be applied to gaseous Hi, Dj, and other rarefied gases of 5 = 1 particles.PACS numbers: 67.65,+z, 51.60.+a, 67.20.+k, 75.30.Ds Spin dynamics of disordered media is a long standing and very intriguing problem in physics of magnetic phenomena. The most typical example of the system in question is a paramagnetic fluid. Spin dynamics of a quantum Fermi liquid of particles with spin y (electrons in metals, liquid 3 He, dilute 3 He-4 He mixtures, etc.) has been studied in detail both in theory and experiment (e.g., see [1][2][3][4][5][6][7][8][9][10][11][12]). A remarkable fact is that weakly damped collective oscillations of magnetization can propagate in a polarized paramagnetic fluid even in the low density limit and at high temperatures, i.e., in rarefied Maxwell-Boltzmann gases [13][14][15][16][17]. At the microscopic level the phenomenon is of a purely quantum-mechanical origin and may be understood in terms of the exchange effects in refraction of the wave function despite the fact that from the viewpoint of particle statistics the classical temperature range is considered. Nuclear spin waves were observed in experiments with spin-polarized atomic hydrogen Hj [18], gaseous 3 He| [19], and nondegenerate weak solutions of 3 He| in superfluid 4 He [8,10,11].On the other hand, it is rather obvious that spin dynamics of a system of particles (or excitations) with spin larger than y is more complicated and does not reduce to the equations of motion for total magnetization only. It is known that in the case of S = y any function of the spin operator S reduces to a linear in S function. That is why the distribution function ns(p) contains only two terms: the spin-independent one and the part proportional to S. When substituted into the transport equation a distribution function of this kind generates the equations of motion for density and magnetic moment. However, the situation entirely changes if S > y. In this case the powers from 1 up to 25 of the spin operator S are independent, and the distribution function «s(p) contains 25+ 1 independent terms which, in general, may produce the independent equations of motion for all 25 +1 components. Two of them correspond to density and spin dynamics. What about the rest of them?The equations of motion for the remaining components do not coincide with the ordinary Landau-Lifshitz equation for the magnetization in a general case and may pro-vide extra branches of elementary excitations in a magnetic system. Of course, the question of whether some new kinds of weakly damped collective modes can propagate in the system is the most interesting one and the cornerstone of the theory. The problem in question pertains to any system of 5 >: 1 particl...

show abstract

Multiple spin echoes in spin polarized Fermi liquids

Cited by 14 publications

References 7 publications

Echo trains in pulsed electron spin resonance of a strongly coupled spin ensemble

Echo trains in pulsed electron spin resonance of a strongly coupled spin ensemble

A pulsed NMR study of 3He-4He solutions

Quadrupole spin oscillations in polarized rarefied media

Contact Info

Product

Resources

About